Chapter 46 – The Global Ecosystem

biogeochemical cycles - Movement of inorganic elements such as nitrogen,

phosphorus, and carbon through living organisms and the physical environment.

eutrophication - The addition of nutrient materials to a body of water, resulting in

changes in ecological processes and species composition therein.

dead zones – Regions in aquatic ecosystems that are devoid of aquatic life because

eutrophication has resulted in severe oxygen depletion.

greenhouse effect – The warming of Earth that results from retention of heat in its

atmosphere; caused by the presence of greenhouse gases in the atmosphere.

greenhouse gases – Gases in the atmosphere, such as carbon dioxide and methane,

that are transparent to sunlight, but trap heat radiating from Earth’s surface, causing

heat to build up at Earth’s surface.

enhanced greenhouse effect – An increase in the natural process of the greenhouse

effect, brought about by human activities, whereby greenhouse gases such as carbon

dioxide, methane, chlorofluorocarbons and nitrous oxide are being released into the

atmosphere at a far greater rate than would occur through natural processes and thus

their concentrations are increasing. (Also called anthropogenic greenhouse effect or

climate change.)

Chapter 45 – Ecological Communities

community – Any ecologically integrated group of species of microorganisms, plants,

and animals inhabiting a given area.

species composition or diversity – The particular mix of species a community

contains and the abundances of those species.

succession – The gradual, sequential series of changes in the species composition of

a community following a disturbance.

primary succession – one of two types of biological and ecological succession of

plant life, occurring in an environment in which new substrate devoid of vegetation and

usually lacking soil, such as a lava flow or area left from retreated glacier, is deposited.

secondary succession – The ecological succession that occurs on a preexisting soil

after the primary succession has been disrupted or destroyed due to a disturbance that

reduced the population of the initial inhabitants.

energy flow – also called the calorific flow, refers to the flow ofenergy through a food

chain. In an ecosystem, ecologists seek to quantify the relative importance of different

component species and feeding relationships.

trophic level – A group of organisms united by obtaining their energy from the same

part of the food web of a biological community.

producers – an  autotrophic organism capable of producing complex organic

compounds from simple inorganic molecules through the process

of photosynthesis (using light energy) or through chemosynthesis (using chemical

energy).

autotroph – An organism that is capable of living exclusively on inorganic materials,

water, and some energy source such as sunlight (photoautotrophs) or chemically

reduced matter (see chemolithotrophs). (Contrast with heterotroph.)

heterotroph – An organism that requires preferred organic molecules as food.

(Contrast with autotroph.)

primary producer – A photosynthetic of chemosynthetic organism that synthesizes

complex organic molecules from simple inorganic ones.

primary consumer – An organism (herbivore) that eats plant tissues.

tertiary consumer – Carnivores that consume primary carnivores (secondary

consumers).

keystone species – a species on which other species in an ecosystem largely depend,

such that if it were removed the ecosystem would change drastically.

food webs – The complete set of food links between species in a community; a

diagram indicating which ones are the eaters and which are eaten.

carnivores – An organism that eats animal tissues. (Contrast with detritivore, frugivore,

herbivore, omnivore.)

omnivores – An organism that eats both animal and plant material. (Contrast with

carnivore, detritivore, herbivore.)

decomposers – An organism that metabolizes organic compounds in debris and dead

organisms, releasing inorganic material; found among the bacteria, protists, and fungi.

See also detritivore, saprobe.

detritivore – An organism that obtains its energy from the dead bodies or waste

products of other organisms.

ecological efficiency (10% rule) – The overall transfer of energy from one trophic level

to the next, expressed as the ratio of consumer production to producer production.

gross primary productivity (GPP) – The rate at which the primary producers in a

community turn solar energy into stored chemical energy via photosynthesis.

net primary productivity (NPP) – The rate at which energy captured by

photosynthesis is incorporated into the bodies of primary producers through growth and

reproduction.

species richness – The total number of species living in a region.

species diversity – a measure of the diversity within an ecological community that

incorporates both species richness (the number of species in a community) and the

evenness of species' abundances. Species diversity is one component of the concept

of biodiversity.

Chapter 44 – Ecological and Evolutionary Consequences of Species Interactions

interspecific interaction – Interactions between members of different species.

intraspecific competition – Competition among members of the same species.

(Contrast with interspecific completion.)

interspecific competition – Competition between members of two or more species.

(Contrast with intraspecific competition.)

limiting resource – A limiting factor limits the growth or development of an organism,

population, or process.

resource partitioning – A situation in which selection pressures resulting from

interspecific competition cause changes in the ways in which the competing species

uses the limiting resource, thereby allowing them to coexist.

symbiosis – The living together of two or more species in a prolonged and intimate

relationship.

mutualism – A type of interaction between species that benefits both species.

commensalism – A type of interaction between species in which one participant

benefits while the other is unaffected.

parasitism – a relationship between two things in which one of them (the parasite)

benefits from or lives off of the other, like fleas on your dog.

amensalism – Interaction in which one animal is harmed and the other is unaffected.

(Contrast with commensalism, mutualism.)

extinction – The termination of a lineage of organisms.

invasive species – An exotic species that reproduces rapidly, spreads widely, and has

negative effects on the native species of the region to which it has been introduced.

Chapter 43 – Populations

population density – The number of individuals in a population per unit of area or

volume.

geographic range – The region within which a species occurs.

habitat – The particular environment in which an organism lives. A habit patch is an

area of a particular habitat surrounded by other habitat types that may be less suitable

for the organism.

growth rate – The rate, or speed, at which the number of organisms in

a population increases.

mortality – the state of being subject to death.

fecundity – The average number of off-spring produced by each female.

intrinsic rate of increase - A measure of the rate of growth of a population. This is the

instantaneous rate of change (per individual per time interval), assuming the population

is in stable age distribution.

exponential population growth – See multiplicative growth.

multiplicative growth – Population growth in which a constant multiple of the

population size is added to the population during successive time intervals. Also known

as exponential growth. (Contrast with additive growth.)

carrying capacity (K) – The number of individuals in a population that the resources of

its environment can support.

logistic population growth – Growth, especially in the size of an organism or in the

number of organisms in a population, that slows steadily as the entity approaches its

maximum size. (Contrast with multiplicative growth.)

metapopulation – A population divided into subpopulations, among which there are

occasional exchanges of individuals.

dispersion - the pattern of distribution of individuals within a habitat.

immigration – Migration into a place (especially migration to a country of which you are

not a native in order to settle there).The body of immigrants arriving during a specified

interval; the increased immigration strengthened the colony.

The movement of organisms to a specific area, perhaps, for example,

an upstream aquatic environment to further downstream.

emigration – The deliberate and usually oriented departure of an organism from the

habitat in which it has been living.

density – dependent factors – Pertaining to a factor with an effect on population size

that increases in proportion to population density.

density – independent factors – Pertaining to a factor with an effect on population

size that acts independently of population density.

wildlife corridor – a link of wildlife habitat, generally native vegetation, which joins two

or more larger areas of similar wildlife habitat. Corridors are critical for the

maintenance of ecological processes including allowing for the movement of animals

and the continuation of viable populations.

Chapter 42 – Organisms in their Environment

abiotic – Nonliving. (Contrast with biotic.)

biotic – Alive. (Contrast with abiotic.)

ecological system – One or more organisms plus the external environment with which

they interact.

ecology – The scientific study of the interaction of organisms with their living (biotic)

and nonliving (abiotic) environments.

population – Any group of organisms coexisting at the same time and in the same

place and capable of interbreeding with one another.

community – Any ecologically integrated group of species of microorganisms, plants,

and animals inhabiting a given area.

landscapes - A portion of land or territory which the eye can comprehend in

a single view, including all the objects it contains.

biosphere – All regions of Earth (terrestrial and aquatic) and Earth’s atmosphere in

which organisms can live.

ecosystem – The organisms of a particular habitat, such as a pond or forest, together

with the physical environment in which they live.

weather – The state of atmospheric conditions in a particular place at a particular time.

(Contrast with climate.)

climate – The long-term average atmospheric conditions (temperature, precipitation,

humidity, wind direction and velocity) found in a region. (Contrast with weather.)

seasonality – A aspect of climate characterized by fluctuations in temperature over the

course of a year.

adiabatically – occurring without gain or loss of heat

adiabatic cooling - A decrease in air temperature that occurs when air rises and then

expands as pressure decreases at higher altitudes.

Hadley cells – Patterns of vertical atmospheric circulation that influence surface winds

and precipitation patterns according to latitude.

current – Circulation patterns in the surface waters of oceans driven by the prevailing

winds.

climate diagram – A way of graphically summarizing the climate in a given location by

superimposing graphs of average monthly temperature and average precipitation

through a year.

topography – The variations in the elevation of Earth’s surface that form, for example,

mountains and valleys.

biome – A major division of the ecological communities of Earth, characterized primarily

by distinctive vegetation. A given biogeographic region contains many different biomes.

permafrost – a thick subsurface layer of soil that remains frozen throughout the year,

occurring chiefly in polar regions.

tundra – a vast, flat, treeless Arctic region of Europe, Asia, and North America in which

the subsoil is permanently frozen.

boreal forest (taiga) - (also known as the taiga, a russian word meaning swampy

moist forest) is found in a nearly continuous belt across North America and Eurasia.

Most of Canada and Russia are covered by coniferous trees that make up this biome.

This biome is defined mainly by the trees that compose it.

temperate rain forest - are coniferous or broadleaf forests that occur in the temperate

zone and receive high rainfall.

temperate deciduous -  temperate broad-leaf forests are dominated by trees that lose

their leaves each year. They are found in areas with warm, moist summers and mild

winters.

temperate grassland – Temperate grasslands are composed of a rich mix of grasses

and forbs and underlain by some of the world’s most fertile soils. Since the development

of the steel plow most have been converted to agricultural lands.

chaparral – vegetation consisting chiefly of tangled shrubs and thorny bushes

desert – a dry, barren area of land, especially one covered with sand, that is

characteristically desolate, waterless, and without vegetation.

savanna - a grassy plain in tropical and subtropical regions, with few trees.

tropical rain forest - an ecosystem type that occurs roughly within the latitudes 28

degrees north or south of the equator. This ecosystem experiences high average

temperatures and a significant amount of rainfall.

plankton – Free-floating small aquatic organisms. Photosynthetic members of the

plankton are referred to as phytoplankton.

nekton - aquatic animals that are able to swim and move independently of water

currents.

benthos – the flora and fauna found on the bottom, or in the bottom sediments, of a

sea, lake, or other body of water.

phytoplankton – Photosynthetic plankton.

zooplankton – plankton consisting of small animals and the immature stages of larger

animals.

flowing-water ecosystems - any type of water that has a constant flow over top of

land. Some examples are waterfalls, creeks, streams, and rivers.

standing-water ecosystems -  Lentic ecosystems such as lakes and ponds that do not

have constant flow over land.

littoral zone – The nearshore region of a lake that is a shallow and is affected by wave

action and fluctuations in water level.

limnetic zone – The open-water region of a lake.

profundal zone - a deep zone of an inland body of freestanding water, such as a lake

or pond, located below the range of effective light penetration. This is typically below the

thermocline, the vertical zone in the water through which temperature drops rapidly.

freshwater wetlands –  areas filled with surface or ground water such as ponds,

swamps, bogs, and marshes. Topography: Found in valleys or other low areas and has

a high water table in early winter and spring.

ecosystem services – Processes by which ecosystems maintain resources that benefit

human society.

estuary – the tidal mouth of a large river, where the tide meets the stream.

salt marshes - an area of coastal grassland that is regularly flooded by seawater.

mangrove forests – Mangrove ecology is the study of biotic interactions

within mangrove swamp ecosystems. These habitats are significant not only for the

biodiversity they represent, but also for the protection of coastal erosion, and for the

provision of protected nursery areas for marine fauna.

intertidal zone – A nearshore region of oceans that is periodically exposed to the air as

the tides rise and fall.

benthic environment – the environment at the bottom of lakes, rivers, estuaries, or

oceans.

benthic zone – The bottom of the ocean.

sea grasses - a grasslike plant that lives in or close to the sea, especially eelgrass.

coral reefs - a ridge of rock in the sea formed by the growth and deposit of coral.

neritic province – the relatively shallow part of the ocean above the drop-off of the

continental shelf, approximately 200m in depth.

euphotic zone - the layer closer to the surface that receives enough light for

photosynthesis to occur.

oceanic province - The water of the ocean that lies seaward of the break in the

continent

marine snow - Particles of mostly organic debris, such as dead or decomposed

organisms, fecal matter, and sand, that drift downward through the ocean from the

upper levels, serving as a food source for a variety of organisms inhabiting the deeper

regions where sunlight does not reach.

eutrophic - (of a lake or other body of water) rich in nutrients and so supporting a

dense plant population, the decomposition of which kills animal life by depriving it of

oxygen.

ecotone – a region of transition between two biological communities.

Chapter 41 – Animal Behavior

ethology – An approach to the study of animals behavior that focuses on studying

species in natural environments and questions about the evolution of behavior.

(Compare with behaviorism.)

behavorial biology – Studying behavior in the natural setting.

behaviorism – One of two classical approaches to the study of proximate causes of

animal behavior, derived from the discoveries of Ivan Pavlov and focused on laboratory

studies. (Compare with ethology.)

proximate and ultimate causes – A proximate cause is an event which is closest to, or

immediately responsible for causing, some observed result. This exists in contrast to a

higher-level ultimate cause (or distal cause) which is usually thought of as the "real"

reason something occurred.

proximate cause – The immediate genetic, physiological, neurological, and

developmental mechanisms responsible for a behavior or morphology. (Contrast with

ultimate cause.)

ultimate causes – In ethology, the evolutionary processes that produced an animal’s

capacity and tendency to behave in particular ways. (Contrast with proximate cause.)

releasers – Sensory stimulus that triggers performance of a stereotyped behavior

pattern.

cost-benefit analysis – An approach to evolutionary studies that assumes an animal

has a limited amount of time and energy to devote to each of its activities, and that each

activity has fitness costs as well as benefits. (See also trade-off)

adaptive behavior - the collection of conceptual, social, and practical skills that all

people learn in order to function in their daily lives. 

instinctual behavior - an unlearned, inborn tendency to behave in a way characteristic

of a species, ie migration.

imprinting – In animal behavior, a rapid form of learning in which an animal learns,

during a brief critical period, to make a particular response, which is maintained for life,

to some object or other organism.

innate behavior – In animals, one of two general types of defenses against pathogens.

Nonspecific and present in most animals. (Contrast with adaptive immunity.)

fixed action patterns – In ethology, a genetically determined behavior that is

performed without learning, stereotypic (performed the same way each time), and not

modifiable by learning.

releaser – see above

habituation – The disappearance of responsiveness to accustomed stimulation.

operant behavior - any active behavior that operates upon the environment to

generate consequences.

classical conditoning - a learning process that occurs when two stimuli are repeatedly

paired; a response that is at first elicited by the second stimulus is eventually elicited by

the first stimulus alone.

insight learning - A type of learning that uses reason, especially to form conclusions,

inferences, or judgments, to solve a problem.

circadian rhythms – A rhythm of growth or activity that recurs on a yearly basis.

diurnal – of or during the day

nocturnal – of or during the night

crepuscular – (of an animal) appearing or active in twilight.

superchiasmatic nuclei –

suprachiasmatic nuclei (SCN) – In mammals, two clusters of neurons just above the

optic chiasm that act as the master circadian clock.

distal – Away from the point of attachment of other reference point. (Contrast with

proximal.)

sexual selection – Selection by one sex of characteristics in individuals of the opposite

sex. Also, the favoring of characteristics in one sex as a result of competition among

individuals of that sex for mates.

culture – (1) A laboratory association of organisms under controlled conditions. (2) The

collection of knowledge, tools, values, and rules that characterize a human society.

direct fitness - a measure of the number of genes passed on to the next generation

relative to other genetic contributions; individuals maximize their fitness by having as

many offspring as possible that live to reproduce (and contribute their genes to the next

generation)

inclusive fitness – The sum of an individual’s genetic contribution to subsequent

generations both via production of its own off-spring and via its influence on the survival

of relatives who are not direct descendants.

kin selection – That component of inclusive fitness resulting from helping the survival

of relatives containing the same alleles by descent from a common ancestor. (Contrast

with individual fitness.)

Hamilton’s rule – The principle that, for an apparent altruistic behavior to be adaptive,

the fitness benefit of that act to the recipient times the degree of relatedness of the

performer and the recipient must be greater than the cost to the performer.

altruistic behavior - of or pertaining to behavior by an animal that may be to its

disadvantage but that benefits others of its kind, often its close relatives.

altruism – Pertaining to behavior that benefits other individuals at a cost to the

individual who performs it.

cooperative behavior - The interaction of two or more persons or organizations

directed toward a common goal which is mutually beneficial.